Eco-feedback (Environment-specific feedback)

According to practopoiesis, for a system as a whole, to be adaptive each level of organization needs to receive its own feedback from the environment. That is, the triggers that activate monitor-and-act units at any lower level of organization must contain information on how effective is the behavior of the system at the top-most level of organization. That way, the units at lower levels of organization receive information necessary to decide whether to act or not.

We refer to this property of adaptive systems as eco-feedback or environment-specific feedback.

There is a very simple reason for the need that feedback comes from the environment. The very act of adapting presumes not knowing upfront what the environment will be like in the future. Thus, the only way to adjust oneself to unpredictable events is to receive information from the environment concerning how well one is doing at the moment.

Sources of eco-feedback information

This does not mean that the monitor-and-act units must posses a direct assess to environmental information, such as a dedicated sensory organ. Information extracted indirectly is equally useful. This means that any information-extraction “trick” will do that enables the monitor-and-act units to extract the relevant information. For example, relevant information can be extracted from the internal activity of a system provided that this activity is sufficiently affected by the inputs from the environment. We say the information may trickle down along the practopoietic hierarchy.

It is a part of the cybernetic knowledge of a monitor-and-act unit to selectively use those bits of the internal activity that are informative of the outside events. For example, if a concentration of a certain molecule has increased, it may indicate with high reliability that an environment with certain properties has been encountered. Thereupon, low-level mechanisms may act accordingly.

Information trickle-down means that monitor-and-act units at low levels of organization can extract the necessary information from the activity of units at higher levels of organization. For example, the sensory inputs that serve primarily the sensory-motor loops can be used to extract the needed information for lower levels of organization, such as the plasticity mechanisms.